/Engine/Source/Runtime/Engine/Public/MaterialHLSLTree.h
FExpressionParameter ( const [FMaterialParameterInfo](API\Runtime\Engine\FMaterialParameterInfo) & InParameterInfo, const [FMaterialParameterMetadata](API\Runtime\Engine\FMaterialParameterMetadata) & InParameterMeta, EMaterialSamplerType InSamplerType, const [FGuid](API\Runtime\Core\Misc\FGuid) & InExternalTextureGuid )